Moroso 85481 Air/Oil Separator Catch Can Kit for GM Trucks - Compatible with 2014-2018 Silverado/Sierra/Tahoe/Suburban 2500 (Gen IV Gas Engines) | Engine Protection & Performance Upgrade | Ideal for Off-Roading, Towing & Heavy-Duty Use

Installed on 2004 Tahoe. Clear instructions were included. I would deem it a very necessary add-on to better assist the PCV situation with these SUVs as their intake manifolds get coated internally with oil over time. This helps keep oil out of there and it also has a nice drop out valve to drain the collected waste oil for disposal. I would drain it out after every oil change. The stuff that would come out of there would be so nasty. It’s a good thing to have for your engine’s longevity!